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Abstract:

A geothermal based, binary cycle power plant is provided, comprising: a
vaporizer for vaporizing pre-heated organic motive fluid by means of
geothermal steam; two organic vapor turbines operating in parallel and
coupled to a common generator, each of said turbines being driven by
vaporized organic motive fluid supplied to each turbine; two recuperators
for heating the organic motive fluid by means of a corresponding organic
vapor turbine discharge; and two condensers for condensing heat depleted
motive fluid exiting said two recuperators, respectively.
A geothermal steam condensate recovery system is also provided,
comprising a source of geothermal steam for vaporizing a organic motive
fluid and producing geothermal steam condensate, and conduit means
through which geothermal steam condensate is delivered to a supply of
cooling liquid used to condense the organic motive fluid, the delivered
geothermal steam condensate serving as make-up liquid for evaporated
cooling liquid.

Claims:

1. A geothermal based, binary cycle power plant, comprising: a) a
vaporizer for vaporizing pre-heated organic motive fluid by means of
geothermal steam; b) two organic vapor turbines operating in parallel and
coupled to a common generator, each of said turbines being driven by
vaporized organic motive fluid supplied to each turbine; c) two
recuperators for heating the organic motive fluid by means of a
corresponding organic vapor turbine discharge; and d) two condensers for
condensing heat depleted organic motive fluid exiting said two
recuperators, respectively.

2. The power plant according to claim 1, wherein the organic motive fluid
is preheated by means of geothermal fluid.

3. The power plant according to claim 2, wherein the geothermal fluid
which preheats the organic motive fluid is geothermal liquid or brine.

4. The power plant according to claim 2, wherein the geothermal fluid
which preheats the organic motive fluid is heat depleted geothermal steam
or steam condensate exiting the vaporizer.

5. The power plant according to claim 4 including a further pre-heater
for pre-heating organic motive fluid exiting said condensers and
utilizing heat present in further heat depleted geothermal steam or steam
condensate exiting said pre-heater.

6. The power plant according to claim 5, wherein the preheated organic
motive fluid exiting the further pre-heater is supplied is to said
recuperators.

7. The power plant according to claim 6 wherein heated organic motive
fluid condensate exiting said recuperators is combined and the combined
flow is supplied to said pre-heater.

8. The power plant according to claim 1 further comprising a further
vaporizer for vaporizing pre-heated organic motive fluid by means of
geothermal steam.

9. The power plant according to claim 8 wherein said vaporizer is
supplied with pre-heated organic motive fluid pre-heated in a pre-heater
by geothermal liquid or brine and said further vaporizer is supplied with
pre-heated organic motive fluid pre-heated in a further pre-heater by
geothermal steam or steam condensate exiting said further vaporizer.

10. The power plant according to claim 9 wherein said pre-heater is
supplied with organic motive fluid condensate exiting one of said two
recuperators, said one of said two recuperators being supplied with
organic motive fluid condensate exiting the other recuperator.

11. The power plant according to claim 10 wherein said further pre-heater
is supplied with organic motive fluid condensate exiting one of said two
condensers.

12. The power plant according to claim 11 wherein said further pre-heater
is supplied with heat depleted geothermal steam or steam condensate
exiting said two vaporizers.

13. A geothermal steam condensate recovery system, comprising a source of
geothermal steam for vaporizing an organic motive fluid and producing
geothermal steam condensate, and conduit means through which geothermal
steam condensate is delivered to a supply of cooling liquid used to
condense said organic motive fluid, said delivered geothermal steam
condensate serving as make-up liquid for evaporated cooling liquid.

14. The system according to claim 13, further comprising a vaporizer for
vaporizing organic motive fluid by means of the geothermal steam, and a
first pre-heater for preheating organic motive fluid condensate by means
of geothermal steam condensate, wherein the conduit means through which
the geothermal steam condensate is delivered to the supply of cooling
liquid supplies heat depleted geothermal steam condensate from said first
pre-heater.

15. The system according to claim 14, wherein the organic motive fluid
condensate preheated by the first preheater is deliverable to the
vaporizer.

16. The system according to claim 14, wherein the organic motive fluid
condensate preheated by the first preheater is heated by geothermal steam
condensate exiting the vaporizer.

17. The system according to claim 16, wherein the organic motive fluid
condensate preheated by the first preheater is heated by geothermal steam
condensate exiting each of two vaporizers and combined by a common
conduit for supplying the geothermal steam or steam condensate to the
first preheater.

18. The system according to claim 16, further comprising a further
pre-heating heat exchanger means for pre-heating pre-heated organic
motive fluid with geothermal steam or steam condensate exiting said first
pre-heater.

19. The system according to claim 16, wherein the organic motive fluid
condensate preheated by the first preheater is pre-heated by the
geothermal steam or steam condensate exiting said first pre-heater.

20. The system according to claim 19, wherein the first pre-heater
includes a pre-heater heat exchanger means having two stages, the
pre-heater heat exchanger means comprising a first stage which is a
second pre-heater for pre-heating organic motive fluid by means of the
geothermal liquid or brine, and a further pre-heater stage for also
pre-heating organic motive fluid with geothermal steam or steam
condensate exiting the vaporizer.

21. The system according to claim 20, wherein heat depleted brine which
is not mixed with the heat depleted geothermal steam or steam condensate
is reinjected into a reinjection well.

22. The system according to claim 20, wherein the first and further
stages of pre-heater heat exchanger means are separated by a partition.

23. The system according to claim 20, wherein the temperature of the heat
depleted geothermal brine exiting the pre-heater heat exchanger means is
greater than its precipitation point.

24. The system according to claim 13, wherein the organic motive fluid is
an organic fluid of an Organic Rankine Cycle (ORC) type power system.

25. The system according to claim 13, wherein the supply of cooling
liquid is cooled by means of a cooling tower.

26. The system according to claim 13, wherein the geothermal steam
condensate which is not delivered to the supply of cooling liquid is
re-injected into a re-injection well.

27. The system according to claim 18, wherein extracted geothermal fluid
is separated into a steam portion and into a brine portion by means of a
separator.

28. A power plant, comprising the geothermal steam condensate recovery
system according to claim 24.

Description:

FIELD

[0001] The present invention relates to the field of geothermal energy.
More particularly, the invention relates to a geothermal binary cycle
power plant with a system for utilizing geothermal steam condensate.

BACKGROUND

[0002] At many prior art geothermal based power plants, geothermal fluid
exiting production wells is separated into a steam portion and a brine
portion. In binary power plant cycles, the steam portion can be used to
provide latent heat in a vaporizer for producing organic motive fluid
vapor while the geothermal steam condensate produced, together with the
brine may be brought in heat exchanger relation with the motive fluid of
a binary power cycle, e.g. organic motive fluid, for preheating the
motive fluid. The organic motive fluid vapor produced can be supplied to
an organic vapor turbine for producing electricity.

[0003] U.S. Pat. No. 5,664,419 describes an apparatus that comprises a
recuperator for transferring heat from heat depleted organic fluid
produced by an organic vapor turbine to organic condensate produced by an
organic vapor condenser. The heated organic condensate produced by the
recuperator is supplied to a pre-heater which receives brine and steam
condensate from the vaporizer for transferring sensible heat to the
organic fluid before the brine and steam condensate are disposed of while
cooled organic vapor produced by the recuperator is supplied to the
organic vapor condenser. The combined flow of cooled brine and cooled
steam condensate forms a combined flow of diluted, cooled brine for
re-injection into a re-injection well. Thus, in U.S. Pat. No. 5,664,419,
the presence of the recuperator permits additional heat to be used by the
organic working fluid in excess of that transferred directly by the
geothermal fluid in the vaporizer and the preheater, without increasing
the vaporization temperature of the organic fluid. Thus, the exit
temperature of the brine leaving the preheater is no longer the
controlling factor for establishing the amount of heat that can be added
to the working fluid.

[0004] The present invention provides a geothermal steam condensate
recovery system for utilizing the steam condensate in a way that it has
not been exploited heretofore.

[0005] In addition, the present invention provides a geothermal fluid
recovery system for utilizing the brine in a way that it has not been
exploited heretofore.

[0006] Other advantages of the invention will become apparent as the
description proceeds.

SUMMARY

[0007] The present invention is directed to a geothermal based, binary
cycle power plant, comprising a vaporizer for vaporizing pre-heated
organic motive fluid by means of geothermal steam; two organic vapor
turbines operating in parallel and which can be coupled to a common
generator, each of said turbines being driven by vaporized organic motive
fluid supplied to each turbine; two recuperators for heating the organic
motive fluid by means of a corresponding organic vapor turbine discharge;
and two condensers for condensing heat depleted organic motive fluid
exiting said two recuperators, respectively.

[0008] By using two recuperators wherein, in one aspect, the combined
liquid output of the recuperators is used for preheating the organic
motive fluid and wherein, another aspect, one recuperator supplies the
preheated organic motive fluid condensate output to a pre-heater, this
recuperator being supplied with the organic motive fluid condensate
output from the other recuperator, high power efficiency levels and power
output are achieved. In addition, thereby, less heat can be extracted
from the geothermal brine so that the power plant of the present
invention is less sensitive to separation or precipitation of solids from
the geothermal liquid or brine and permits optimal and sustainable
utilization of a geothermal resource. Moreover, in accordance with the
present invention wherein the geothermal liquid or brine and geothermal
steam and condensate are maintained separate from one another, the
temperature of the geothermal steam condensate can be made sufficiently
cool for making it suitable for use as make-up liquid for cooling liquid
supplied to the cooling tower or other suitable uses such as industrial
uses e.g. providing cooling liquid for evaporative cooling of air-cooled
condensers or cooling liquid for fogging or deluge of the cooling pipes
of air-cooled condensers, etc.

[0009] In one aspect, the organic motive fluid is preheated by means of
geothermal fluid, i.e. brine or heat depleted geothermal steam or steam
condensate exiting the vaporizer in pre-heaters. In addition, in a
further aspect, organic motive fluid exiting the condensers is
additionally pre-heated in a further pre-heater utilizing heat in further
heat depleted geothermal steam or steam condensate exiting a pre-heater.

[0010] In one aspect, the power plant further comprises a further
vaporizer for vaporizing pre-heated organic motive fluid by means of
geothermal steam.

[0011] In one aspect, the vaporizer is supplied with pre-heated organic
motive fluid pre-heated in a pre-heater by geothermal liquid or brine and
the further vaporizer is supplied with pre-heated organic motive fluid
pre-heated in a further pre-heater by geothermal steam or steam
condensate exiting the further vaporizer.

[0012] In one aspect, the pre-heater is supplied with organic motive fluid
condensate exiting one of the two recuperators, said one of the two
recuperators being supplied with organic motive fluid condensate exiting
the other recuperator.

[0013] By use of the pre-heaters as well as the recuperators in the power
plant in accordance with an aspect of the present invention, high power
plant efficiency levels are achieved as well as increased power output
levels.

[0014] The present invention also provides a geothermal steam condensate
recovery system, comprising a source of geothermal steam for vaporizing
an organic motive fluid, and conduit means through which geothermal steam
condensate is delivered to a supply of cooling liquid used to condense
said organic motive fluid, said delivered geothermal steam condensate
serving as make-up liquid for evaporated cooling liquid.

[0015] The system further comprises a vaporizer for vaporizing organic
motive fluid by means of the geothermal steam, and a first pre-heater for
pre-heating organic motive fluid condensate by means of geothermal steam
or condensate, wherein the conduit means through which the geothermal
steam condensate is delivered to the supply of cooling liquid supplies
heat depleted geothermal steam condensate from said first pre-heater.

[0016] In one aspect, the organic motive fluid condensate preheated by the
first pre-heater is deliverable to the vaporizer.

[0017] In one aspect, the organic motive fluid condensate preheated by the
first preheater is heated by geothermal steam exiting the vaporizer.

[0018] In one aspect, the organic motive fluid condensate preheated by the
first preheater is heated by geothermal steam or steam condensate exiting
each of two vaporizers and combined by a common conduit supplying the
geothermal steam or steam condensate to the first preheater.

[0019] In one aspect, the system further comprises a further pre-heater
heat exchanger means for pre-heating preheated organic motive fluid with
geothermal steam or steam condensate exiting the first pre-heater.

[0020] In one aspect, the organic motive fluid condensate preheated by the
first preheater is pre-heated by the geothermal steam or steam condensate
exiting the first pre-heater.

[0021] In one aspect, the first pre-heater includes a pre-heater heat
exchanger means having two stages, the pre-heater heat exchanger means
comprising a first stage which is a second pre-heater for pre-heating
organic motive fluid by means of the geothermal liquid or brine, and a
further pre-heater stage for also pre-heating organic motive fluid with
geothermal steam or steam condensate exiting the vaporizer.

[0022] In one aspect, heat depleted brine which is not mixed with the heat
depleted geothermal steam or steam condensate is reinjected into a
reinjection well.

[0023] In one aspect, the first and further stages of pre-heater heat
exchanger means are separated by a partition.

[0024] In one aspect, the temperature of the heat depleted geothermal
brine exiting the pre-heater heat exchanger means is greater than its
precipitation point.

[0025] In one aspect, the organic motive fluid is organic fluid of an
Organic Rankine Cycle (ORC) type power system.

[0026] In one aspect, the supply of cooling liquid is cooled by means of a
cooling tower.

[0027] In one aspect, the geothermal steam condensate which is not
delivered to the supply of cooling liquid is re-injected into a
re-injection well.

[0028] In one aspect, extracted geothermal fluid is separated into a steam
portion and into a brine portion by means of a separator.

BRIEF DESCRIPTION

[0029] In the drawings:

[0030] FIG. 1 is a schematic illustration of a binary cycle power plant
comprising a geothermal steam condensate recovery system, according to
one embodiment of the present invention; and

[0031] FIG. 2 is a schematic illustration of a binary cycle power plant
comprising a geothermal steam condensate recovery system, according to
another embodiment of the present invention.

[0032] Similar reference numerals and symbols refer to similar components.

DETAILED DESCRIPTION

[0033] FIG. 1 illustrates a geothermal based, binary cycle power plant
according to one embodiment of the present invention, and is designated
40. Power plant 40 comprises Organic Rankine Cycle (ORC) type power
system 10 and geothermal steam condensate recovery (SCr) system 30
operable in conjunction with ORC system 10. The dashed lines indicate
conduits or lines through which fluid in a vapor phase flows, and the
solid lines indicate conduits or lines through which a substantially
liquid fluid flows.

[0034] In SCr system 30, a separator (not shown) separates the geothermal
fluid exiting a production well at a temperature of about 120-190°
C. into a steam portion and a liquid or brine portion. The steam portion
is delivered via outlet 5 of the separator and conduit or line 6 to
vaporizer 20, for vaporizing organic motive fluid of an organic motive
fluid power cycle. The heat depleted geothermal steam or condensate
exiting vaporizer 20 flows through conduit or line 21, and is heated
within two-stage pre-heater heat exchanger 12 by means of the brine
portion delivered thereto from outlet 7 of the separator via conduit or
line 8. In first stage A of pre-heater heat exchanger 12, which may be of
the shell and tube type, the separated brine portion preheats the organic
motive fluid recuperator discharge supplied through conduit 61. In stage
B of pre-heater heat exchanger 12, heat depleted geothermal steam or
condensate also provides heat for further pre-heating the organic motive
fluid condensate. The second stage B of pre-heater heat exchanger 12,
wherein a portion, or all, of the heat depleted geothermal steam or
condensate transfers heat to the organic motive fluid in addition to the
brine in first stage A, may be separated from first stage A by partition
19 through which the brine passes. Heat depleted brine which is not mixed
with heat depleted geothermal steam or condensate exits pre-heater heat
exchanger 12 via conduit 16 and is re-injected into a reinjection well
via inlet 9.

[0035] Heat depleted geothermal steam condensate exits second stage B of
pre-heater heat exchanger 12 via conduit or line 17 and is delivered to
additional pre-heater 22, which also preheats the organic motive fluid
condensate supplied thereto. By employing pre-heater 22, further heat
present in geothermal condensate is transferred to the organic motive
fluid supplied to additional pre-heater 22 and therefore the rate of heat
transfer for preheating the organic motive fluid condensate will also be
increased.

[0036] An additional advantage of the aspect of the present embodiment is
that the heat depleted geothermal steam condensate thus having a reduced
temperature may be exploited to provide make-up water for the cooling
tower water supply 49, or for any other suitable use by means of which
the organic motive fluid condensate is heated. Such uses could include
such industrial uses e.g. providing cooling liquid for evaporative
cooling of air-cooed condensers or cooling liquid for fogging or deluge
of the cooling pipes of air-cooled condensers, etc. Some of the
geothermal steam condensate exiting additional pre-heater 22 via conduit
or line 23 is diverted to conduit 26, from which the geothermal steam
condensate is delivered to main cooling liquid supply conduit 64
extending from cooling liquid supply 49, to serve as make-up water for
the cooling liquid that was evaporated. The remaining portion of the
geothermal steam condensate is re-injected into a re-injection well via
supply 25.

[0037] While prior art power plants require a source of make-up cooling
liquid, which significantly adds to the operating costs of the plant, the
heretofore unexploited geothermal steam condensate resource normally
reinjected into a re-injection well can provide much benefits to the
power plant in terms of assisting in condensing the organic motive fluid,
obviating the need of make-up cooling liquid, and preheating the
condensed organic motive fluid.

[0038] The operating conditions of power plant 40, particularly of each
organic fluid condenser and of pre-heater heat exchanger means 12, may be
suitably selected to ensure that the temperature of the geothermal liquid
or brine exiting pre-heater heat exchanger means 12 will be greater than
its precipitation point. Maintaining the geothermal liquid or brine above
its precipitation point will prevent undesired corrosion and scaling onto
the metallic conduit and heat exchanger surfaces of significant
quantities of silica, chlorides, and carbonates that are typically
dissolved in the geothermal liquid.

[0039] In ORC system 10, the discharge from two organic turbines 53 and 55
operating in parallel and advantageously coupled to a common generator 59
is delivered to recuperators 63 and 65, respectively, via conduits 64 and
66, respectively. The heat depleted organic fluid vapor exiting
recuperators 63 and 65 is delivered to condensers 33 and 35,
respectively, via conduits 31 and 32, respectively. Organic condensate is
produced by providing cooling liquid, which is supplied through conduits
or lines 71 and 74 branching from main cooling liquid supply conduit or
line 64, to condensers 33 and 35, respectively. The heated cooling liquid
exits condensers 33 and 35 via conduits 41 and 43, respectively, leading
to the cooling liquid conduit 75 which extends to return inlet 77 of the
cooling tower. Electric generator 59 and other rotating components
included in power plant 40 may be cooled by means of auxiliary cooling
supply 81, which receives cooling liquid from main cooling liquid supply
conduit 64 and discharges heated cooling liquid to conduit 75.

[0040] The organic motive fluid condensate discharged from organic motive
fluid condensers 33 and 35 through conduits 34 and 36, respectively, is
directed to common conduit 38, pressurized by organic motive fluid
condensate pump 37, and delivered to preheater 22. The preheated organic
motive fluid condensate flows through conduit 29 and then branches into
conduits 67 and 68 extending to recuperators 63 and 65, respectively. The
enthalpy of the preheated organic motive fluid condensate is increased by
means of the corresponding organic motive fluid vapor turbine discharge
delivered to recuperators 63 and 65, and is further increased, after
flowing through conduits 51, 52, and 61, by means of the brine flowing
through first stage A of pre-heater heat exchanger 12 and also steam
condensate flowing through further stage B of pre-heater heat exchanger
12. The heated organic motive fluid is then delivered via conduit 18 from
first stage A of heat exchanger 12 to vaporizer 20. In vaporizer 20, the
organic motive fluid is vaporized by the geothermal steam portion, and is
delivered via conduits or lines 47 and 48 to organic motive fluid vapor
turbines 53 and 55, respectively. Non-condensable gases (NCG) if produced
can be bled off via conduit 28 to drive the cooling tower fans.

[0041] The heat influx transferred to the organic fluid by the brine in
two stages, i.e. by geothermal liquid or brine in first stage A and by
the steam condensate in further stage B of pre-heater heat exchanger 12
as well as in pre-heater 22, sufficiently heats the organic fluid such
that the heat capacity of the geothermal steam can be utilized to
generate enough vapor to drive two turbines operating in parallel. The
discharge of each of the two turbines operating in parallel is also
utilized to further add to the heat influx provided to the organic fluid
by means of recuperators 63 and 65. Furthermore, by using steam
condensate in 2 pre-heaters, the steam condensate is cooled sufficiently
to make it suitable for use as make-up water for the cooling liquid in
the cooling tower.

[0042] While one geothermal based, binary cycle power plant 40 is
described above in this embodiment, advantageously, in accordance with
this embodiment of the present invention, a plurality of such binary
cycle power plants can be used.

[0043] FIG. 2 illustrates another embodiment of the invention wherein
geothermal based, binary cycle power plant 140 also comprises an ORC
system 110 provided with two turbines 153 and 155 operating in parallel
and a SCr system 130 operable in conjunction with ORC system 110;
however, in this embodiment, two vaporizers 119 and 120 are employed to
supply organic motive fluid vapor to organic vapor turbines 153 and 155,
respectively, and two recuperators 163 and 165 supply organic fluid in
series exiting recuperator 165.

[0044] In SCr system 130, a separator (not shown) separates the geothermal
fluid from a production well into a steam portion and a liquid or brine
portion. The separated steam portion flows via outlet 105 of the
separator and conduit or line 106, the latter branching into conduits or
lines 111 and 113 through which the steam is delivered to vaporizers 119
and 120, respectively, for producing organic fluid vapor. The flow of
heat depleted geothermal steam or steam condensate exiting vaporizers 119
and 120 via conduits or lines 121 and 124, respectively, is combined and
the combined flow of heat depleted geothermal steam or steam condensate
is supplied through conduit or line 127 to steam condensate pre-heater
122, for transferring the heat present in both heat depleted geothermal
steam or steam condensate flows in conduits or lines 121 and 124,
respectively, for pre-heating the organic motive fluid condensate
delivered from organic condenser 135 by means of pump 137 via conduit 136
and thereby cooling the heat depleted geothermal steam or steam
condensate.

[0045] The cooled geothermal steam condensate is also exploited to provide
make-up water for cooling liquid or water supplied to cooling tower 149
or for any other suitable use such as industrial uses e.g. providing
cooling liquid for evaporative cooling of air-cooled condensers or
cooling liquid for fogging or deluge of the cooling pipes of air-cooled
condensers, etc. Some of the geothermal steam condensate exiting
pre-heater 122 via conduit 123 can be diverted to conduit 126, from which
the geothermal steam condensate is delivered to main cooling liquid
supply conduit 164 extending from cooling liquid supply 149, to serve as
make-up water for the cooling liquid that was evaporated. The remaining
portion of the geothermal steam condensate can be re-injected into a
re-injection well via inlet 125.

[0046] The geothermal liquid or brine portion is supplied via outlet 107
of the separator and conduit or line 108 to brine pre-heater 112, for
preheating the organic motive fluid exiting recuperator 165. The heat
depleted geothermal liquid or brine flows through conduit or line 116 and
is reinjected into re-injection well via inlet 109.

[0047] In ORC system 110, the discharge from the two organic vapor
turbines 153 and 155 operating in parallel and advantageously coupled to
a common generator 159 is delivered to recuperators 163 and 165,
respectively, via conduits or lines 164 and 166, respectively. The heat
depleted organic motive fluid exiting recuperators 163 and 165 is
delivered to condensers 133 and 135, respectively, via conduits or lines
131 and 132, respectively, and is condensed by means of the cooling
liquid flowing through conduits 171 and 174, respectively. The heated
cooling liquid exits condensers 133 and 135 via conduits or lines 141 and
143, respectively, and supplied via cooling liquid conduit 175 to return
inlet 177 of the cooling tower. Auxiliary cooling supply 181 receives
cooling liquid from main cooling liquid supply conduit 164 and discharges
heated cooling liquid to conduit 175.

[0048] The organic condensate discharged from organic motive fluid
condenser 133 by means of pump 138 via conduit 134 is delivered to
recuperator 163. After being heated by the discharge of organic vapor
turbine 153 in recuperator 163, the heated organic motive fluid
condensate flows through conduit 139 and is additionally heated by means
of the discharge of organic vapor turbine 155 in recuperator 165. The
heated organic motive fluid condensate is then supplied from the outlet
of recuperator 165 via conduit 161 to geothermal liquid or brine
pre-heater 112, from which the pre-heated organic motive fluid is
supplied to vaporizer 119 via conduit 118. The vaporized organic motive
fluid is supplied to organic vapor turbine 153 via conduit or line 147.
Thus, due to the heat supplied to the organic motive fluid in recuperator
163 as well as in recuperator 165, less heat can be extracted from the
geothermal liquid or brine in pre-heater 112, consequently allowing the
temperature of the geothermal liquid or brine to be maintained above a
temperature where precipitation or separation of solids from the
geothermal liquid or brine.

[0049] The organic motive fluid condensate discharged from organic motive
fluid condenser 135 via conduit 136 is supplied to steam condensate
pre-heater 122 using pump 137. The pre-heated organic motive fluid
produced therein is supplied via conduit or line 117 to vaporizer 120,
after which the vaporized organic motive fluid is supplied to organic
vapor turbine 155 via conduit 148. Non condensable gases produced from
the geothermal steam in vaporizers 119 and 120 is bled off via conduits
128 and 129, respectively, to using the cooling tower fans.

[0050] While one geothermal based, binary cycle power plant 140 is
described above in this embodiment, advantageously, in accordance with
this embodiment of the present invention, a plurality of such binary
cycle power plants can be used.

[0051] While some embodiments of the invention have been described by way
of illustration, it will be apparent that the invention can be carried
out with many modifications, variations and adaptations, and with the use
of numerous equivalents or alternative solutions that are within the
scope of persons skilled in the art, without departing from the spirit of
the invention or exceeding the scope of the claims.